In the manufacture of tissue products such as facial tissues, bath tissues and paper towels, the tissue basesheets are generally produced by depositing an aqueous suspension of papermaking fibers onto a forming fabric, dewatering the suspension to form a web, drying the web, and winding the dried web into a roll for subsequent conversion into a particular product form. During manufacturing, most tissue webs are adhered to a steam-heated Yankee dryer and thereafter dislodged from the surface of the Yankee by contacting a doctor blade (creping) to improve the softness and stretch of the sheet. More recently, soft uncreped throughdried tissue sheets have been disclosed in which the softness and stretch are built into the sheet by other processing methods.
However, in all such processes, the final dried sheet traverses an "open draw" before being wound into rolls, meaning that the dried sheet is momentarily unsupported before being wound. In the case of creped sheets, the sheet is dislodged from the creping cylinder and passed unsupported from the creping cylinder to the reel. For uncreped throughdried sheets, the sheet leaves the throughdrying fabric, or a subsequent transfer fabric, and also passes unsupported to the reel. As those in the tissue manufacturing business know, these unsupported runs or open draws are a source of sheet breaks and production delay time. To compensate, the tissue sheets are designed to have high machine direction strengths in order to remain intact during manufacturing. However, such high strengths are often counterproductive in terms of softness and are not desirable to the end user of the product.
Therefore, if open draws in tissue manufacturing could be eliminated, tissues could be made more efficiently from a waste-and-delay standpoint and the machine direction strength of the final product could be reduced to levels dictated solely by product requirements rather than manufacturing requirements.